Solubilized lignosulfonate derivatives

Abstract

Valuable new and widely used compositions of matter are comprised of products having enhanced solubility and increased dispersant and the like surfactant activity which products are resulfonated units of alkaline oxidized, hydrolyzed, partially desulfonated lignosulfonates.

What is claimed is: 
     
       1. A composition comprising: a lignosulfonate or an alkali metal salt derivative thereof derived from sulfite waste liquor that has been subjected to alkaline oxidation, hydrolysis and partial desulfonation with subsequent resulfonation;   said lignosulfonate prior to resulfonation being characterized by a relative molecular size of substantially within the range of 1,000 to 20.,000 and containing combined organic sulfonic sulfur after partial desulfonation of from about 0.5 weight percent to about 5.0 weight percent and from about 1.5 percent to 15 percent by weight of said total combined sulfur upon completion of said resulfonation.   
     
     
       2. A composition comprising: an alkaline oxidized hydrolyzed, partially desulfonated and subsequently resulfonated lignosulfonate;   said resulfonated lignosulfonate having substituted therein, as the resulfonation units, those of the formula:   --(CH 2 ) x  --SO 3  H, wherein x has a numerical integral value from 0 to 3; or alkali metal salt derivatives thereof; and   said resulfonated lignosulfonate containing between about 11/2 weight percent and about 15 weight percent of total sulfur in combined organic sulfonic sulfonate form; said lignosulfonate prior to resulfonation having a relative molecular size of substantially 1000 to 20,000.   
     
     
       3. The composition of claim 2, wherein there is between avout 23/4 and about 10 wt. % of said total combined sulfur. 
     
     
       4. The composition of claim 2, wherein there is between about 41/2 and about 61/2 % of said total combined sulfur. 
     
     
       5. The composition of claim 2, wherein said resulfonation unit is a sulfomethyl group of the formula --(CH 2 )SO 3  H. 
     
     
       6. The composition of claim 2 in the form of an alkali metal salt. 
     
     
       7. The composition of claim 2 in the form of a sodium salt. 
     
     
       8. The composition of claim 2 and further characterized in having a relatively constant relative molecular size range with molecular size variations in the composition being within not more than about a 20% volumetric molecule size to molecule size variation one from another. 
     
     
       9. A composition in accordance with the composition of claim 8 wherein said relative molecular size range variation from molecule to molelcule in the composition is not more than about 10 volumetric %. 
     
     
       10. The composition of claim 2, and further characterized in having the inroduced sulfonate units substituted at least substantially in the resulfonated alkaline oxidized, hydrolyzed, partially desulfonated lignosulfonate material in ortho or para locations, or both, on the aromatic rings of the lignin molecules in the resulfonated, partially desulfonated lignosulfonate material of said composition. 
     
     
       11. A composition in accordance with the composition of claim 10, wherein said substituted introduced sulfonate units are located predominently in the ortho or para, or both, locations of said aromatic lignin molecule rings. 
     
     
       12. A composition as claimed in claim 1 wherein said combined organic sulfonic sulfur is present upon completion of resulfonation in an amount by weight of from 2.75 percent to about 10 percent by weight. 
     
     
       13. A composition as claimed in claim 12 wherein said combined organic sulfonic sulfur is present upon completion of resulfonation in an amount by weight of from about 4.5 percent to about 6.5 percent by weight. 
     
     
       14. A composition as claimed in claim 1 wherein said resulfonation is undertaken in an aqueous medium and in the presence of a reactant composition comprising about 5 percent to 40 percent, by weight of said desulfonated lignosulfonate, of alkali metal sulfite. 
     
     
       15. A composition as claimed in claim 14 wherein said sulfite is an alkali metal bisulfite. 
     
     
       16. A composition as claimed in claim 15 wherein said sulfite is sodium bisulfite. 
     
     
       17. A composition as claimed in claim 14 wherein said reactant composition includes one or more aldehydes of the formula: ##STR2## wherein R is hydrogen or an alkyl group containing from 1 to 3 carbon atoms. 
     
     
       18. A composition as claimed in claim 17 wherein said aldehyde is formaldehyde. 
     
     
       19. A composition as claimed in claim 18 wherein said formaldehyde is present in an amount by weight of said partially desulfonated lignosulfonate of about 1.5 percent to 12 percent. 
     
     
       20. A composition as claimed in claim 18 wherein said formaldehyde is present with an alkali metal bisulfite in approximately stoichiometric proportions. 
     
     
       21. A composition as claimed in claim 20 wherein said stiochiometric proportions of formaldehyde to bisulfite may vary by up to 20 percent. 
     
     
       22. A composition as claimed in claim 1 wherein said lignosulfonate after resulfonation is characterized in being substantially completely soluble in each of aqueous saline solutions and acid media having a pH of at least about 1.5. 
     
     
       23. A composition as claimed in claim 1 wherein said lignosulfonate prior to resulfonation is characterized by a pH in aqueous solution of 8.5 percent to 9.2 percent; a total sulfur content 2.5 percent to 2.9 percent by weight; the absence of reducing sugars; and a lignosulfonate content of at least 99 percent by weight. 
     
     
       24. A composition as claimed in claim 1 wherein said lignosulfonate is further characterized by a methoxyl content of from 12.4 to 12.9 weight percent. 
     
     
       25. A composition as claimed in claim 23 wherein said resulfonated lignosulfonate has a relative molecular size of 4200. 
     
     
       26. A composition as claimed in claim 23 wherein said resulfonated lignosulfonate has a relative molecular size of about 3500. 
     
     
       27. A composition as claimed in claim 22 wherein said aqueous saline solution contains relatively large concentrations of sodium chloride and said acid media comprises an aqueous sulfuric acid solution at a pH within the range of about 1.5 and less than 7. 
     
     
       28. A composition as claimed in claim 1 wherein said resulfonation is accomplished in an aqueous reaction mass at a temperature between about 50° and about 200° C. using, for the resulfonation agents, an aldehyde of the formula: ##STR3## wherein R is hydrogen or an alkyl group containing from 1 to 3 carbon atoms in approximately stoichiometric admixture with a sulfite of the formula:   XHSO.sub.3      wherein X is an alkali metal.